React Native ML Kit — Smart Reply

@nitro-mlkit/smart-reply · on-device Google ML Kit via Nitro Modules — JSI, no bridge.

⚠️ Beta (0.1.0-beta.x). Android verified on-device. Android-only — see Platform status.

High-performance, on-device Smart Reply for React Native, built with Nitro Modules (JSI, no bridge).

Powered by Google ML Kit. Given a chat conversation, suggests up to 3 short, contextual replies for the local user — the "Sure!", "Sounds good 👍", "What time?" chips you see in messaging apps. English only. All on-device.

Installation

npm install @nitro-mlkit/smart-reply react-native-nitro-modules

No config plugin (autolinked Expo module). Install and npx expo prebuild. Not available in Expo Go.

Usage

import {
  NitroSmartReply,
  SmartReplyStatus,
  type ConversationMessage,
} from "@nitro-mlkit/smart-reply";

// Order oldest → newest. End with a REMOTE-user message (the one you reply to).
const conversation: ConversationMessage[] = [
  { text: "Hey! Want to grab lunch today?", timestamp: Date.now(), isLocalUser: false, userId: "friend" },
];

const result = await NitroSmartReply.suggestReplies(conversation);

if (result.status === SmartReplyStatus.SUCCESS) {
  console.log(result.suggestions); // e.g. ["Sure!", "Sounds good", "What time?"]
}

NitroSmartReply.isAvailable(); // true on Android, false elsewhere

ConversationMessage

| field | type | notes | | ----- | ---- | ----- | | text | string | the message text | | timestamp | number | Unix ms when the message was sent | | isLocalUser | boolean | true = you; false = the other participant | | userId? | string | required for remote messages; distinguishes participants |

SmartReplyStatus

• SUCCESS — suggestions holds up to 3 replies.
• NO_REPLY — the model had nothing good to suggest.
• NOT_SUPPORTED_LANGUAGE — conversation isn't in a supported language (English only today).

Platform status

| Platform | Min | Status | | -------- | --- | ------ | | Android | API 26+ | ✅ Verified on-device (Pixel 9, API 36) | | iOS | — | ❌ Not supported — Google ML Kit has no Smart Reply API on iOS |

isAvailable() returns false on iOS and suggestReplies() rejects there, so you can call it safely from cross-platform code and gate on the result.

Part of nitro-mlkit

The full ML Kit suite on Nitro — see the other @nitro-mlkit/* packages.

License

MIT © Gonzalo Polo